[swarmee]

Interesting contention. On a case where they have a duplicate cert number, they ask both cards to be sent in to be verified (or high res scans of each).

If the original owner in the PSA Set Registry contends they still own the card with the same cert number, then both cards are requested to be sent back to PSA to verify which one is real. That didn't seem to happen in this case, as the Jordan rookie is highly liquid and could have been sold by the original registry owner, so when Spence put in the request to have it added, they agreed to remove it.
So PSA didn't need both cards in hand, per their usual processes.

Sometimes PSA has found two real cards both originally graded by them with the same cert (mechanical error), and reslabbed both in new holders, giving one card a new Cert #. Sometimes they find counterfeits this way as well, which would have helped Mr. Spence.